Hi Brad. Unfortunately, part of your question was cut off. I am assuming you are asking how your agent earns a commission if you buy from a developer. Most builders will at least pay a referral fee, but then your agent will not be the one who represents you. These days, many developers/builders will pay buyer's agents a full commission because they want to move their inventory. Some even pay higher than average commissions to give the agents an incentive to show their homes to their buyers. You should ask your agent to check with the builders that you have in mind before you even start looking so that your agent can make sure that the proper procedures are followed.
In my opinion, it is very important for buyers to have their own buyer's agent when buying any real estate. When you just buy through the builder's sales office, you'll deal with someone who is employed by the builder and that agent may not look out for your best interest as well as an independent buyer's agent. Best of luck to you.